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Chemical Additives

The term "chemical additive" means a chemical product (including products of disassociation and degradation, collectively "products") introduced into a waste stream that is used for cleaning, disinfecting, or maintenance and which may be detected in effluent discharged to waters of the Commonwealth. The term generally excludes chemicals used for neutralization of waste streams, the production of goods, and treatment of wastewater. In November 2012, DEP developed a Standard Operating Procedure (SOP) for chemical additives. If facilities are known to use chemical additives, then upon reissuance of industrial waste NPDES permits by DEP, the permits will include language that implements the following process:

NOTE: Permittees should always refer to their existing permit for the appropriate chemical additives requirements. The procedures listed above are only applicable to permits issued or reissued after November 2012. However, even if the language is not in the existing permit, permittees are encouraged to review the Approved List and submit requests in preparation for reissued permits.

For those interested in the methods used by DEP to determine aquatic life and human health effect levels for the Approved List, please refer to the DEP Chemical Additives Aquatic Life Calculation Spreadsheet (Excel) and the DEP Chemical Additives Human Health Calculation Spreadsheet (Excel), respectively.

DEP has prepared a presentation (PDF) with additional information on this process. A video tutorial has also been developed to assist industrial facilities. Permittees with questions on chemical additives should contact the DEP regional office that issued the permit or the Bureau of Clean Water at 717-787-5017.

In order to complete the Chemical Additives Notification Form permittees will need to use PENTOXSD, one of DEP's water quality models. For new users, DEP has developed a PENTOXSD Tutorial (WMV) 65.3 MB.

For more information you may contact DEP’s Division of NPDES Permitting at